Valve armature for a solenoid valve, and valve cartridge for a solenoid valve

ABSTRACT

A valve armature assembly of a solenoid valve includes a body, a closing element, and an elastic damping element. The body includes a depression located at an end of the body. The closing element is received in the depression and includes a closing member configured to interact with a valve seat of the valve. The elastic element is positioned in the depression between the closing element and the body and is configured to damp a pulse resulting from the closing member striking the valve seat.

This application is a 35 U.S.C. § 371 National Stage Application ofPCT/EP2015/067774, filed on Aug. 3, 2015, which claims the benefit ofpriority to Serial No. DE 10 2014 217 447.3, filed on Sep. 1, 2014 inGermany, the disclosures of which are incorporated herein by referencein their entirety.

FIELD OF INVENTION

The disclosure relates to a valve armature for a solenoid valve and toan associated valve cartridge for a solenoid valve.

BACKGROUND

The state of the art discloses normally open or normally closed solenoidvalves, which are used as inlet valves or outlet valves in a hydraulicunit of a vehicle braking system, for example. The hydraulic unit servesfor performing open and/or closed-loop control operations in an antilockbraking system (ABS) or a traction control system (TCS) or an electronicstability program system (ESP) in order to build up or reduce pressurein corresponding wheel brake calipers. Such solenoid valves comprise asolenoid assembly and a valve cartridge, which comprises a pole body, aguide sleeve connected to the pole body, a valve armature having aclosing element and axially moveable and guided inside the guide sleeveagainst the force of a return spring between a closed position and anopen position, and a valve sleeve connected to the guide sleeve andhaving a valve seat. The valve seat is arranged between at least onefirst flow port and at least one second flow port. The closing elementin the closed position has a sealing interaction with the valve seat andinterrupts a fluid flow between at least the one first flow port and atleast the one second flow port. In the open position the closing elementis lifted off from the valve seat and allows the fluid flow between atleast the one first flow port and at least the one second flow port.Energizing of the solenoid assembly generates a magnetic force, which inan unenergized, open solenoid valve moves the valve armature with theclosing element from the open position into the closed position untilthe closing element meets the corresponding valve seat and seals thelatter. In the unenergized state the return spring moves the valvearmature with the closing element and the closing element lifts off fromthe valve seat and opens the latter. In an unenergized, closed solenoidvalve the valve armature with the closing element is moved from theclosed position into the open position by the energizing of the solenoidassembly and the closing element lifts off from the valve seat and opensthe latter. If the current is switched off, the return spring moves thesolenoid armature with the closing element in the direction of the valveseat until the closing element meets the valve seat and seals thelatter. The solenoid valves described produce a so-called closing noisewhen the closing element, which comprises a hardened closing member thatis embodied as a steel ball, for example, meets the valve seat likewisecomposed of hardened steel.

The published patent application DE 10 2007 051 557 A1, for example,describes a normally closed solenoid valve for a vehicle hydraulicbraking system with wheel-slip control. The solenoid valve comprises ahydraulic part, also referred to as a valve cartridge, which ispartially arranged in a stepped bore of a valve block, and an electricalpart, which is substantially formed from a solenoid assembly, which isfitted onto the part of the valve cartridge projecting from the valveblock. The solenoid assembly comprises a coil shell with an electricalwinding, a coil casing that carries magnetic flux, and an annular diskthat carries magnetic flux. The hydraulic part comprises a guide sleeve,which at its end facing the electrical part is closed by a pole bodythat is pressed in and welded so that it is fluid-tight. Alongitudinally displaceable armature, which is supported by a returnspring on the pole body, is accommodated in the guide sleeve. Remotefrom the pole body, the armature comprises a spherical closing memberarranged in a depression. At the end remote from the pole body, a cuppedvalve sleeve having a cylindrical shell and a base is pressed into theguide sleeve. The valve sleeve has a passage on the base together with ahollow cone-shaped valve seat, which with the closing member forms aseat valve. The seat valve forms a controllable fluid connection betweenthe passage on the base of the valve sleeve and at least one passage inthe shell of the valve sleeve. A radial filter is moreover arrangedexternally on the shell of the valve sleeve, in order to filter dirtparticles out of the fluid flow. The guide sleeve may be calked in thestepped bore of the valve block by means of a fixing bush.

SUMMARY

The valve armature for a solenoid valve according to the disclosure andthe corresponding valve cartridge for a solenoid valve according to thedisclosure by contrast have the advantage that modification of the valvearmature reduces the closing noise that occurs during closing and in thebest case is even capable of eliminating it almost entirely. Through theuse of an elastic damping element between the closing member and thevalve armature, it is possible to damp the pulse that occurs as theclosing member strikes the valve seat, so that the structure-borne noisein the system can advantageously be reduced.

Embodiments of the present disclosure therefore help to improve thenoise/vibration/harshness (NVH) properties of the vehicle by reducingand at best entirely preventing the intrusive noises occurring when thesolenoid valve closes. It is thereby possible to design the vehiclebraking system as a single-box system and to bolt the hydraulic unitdirectly to the splash wall of the vehicle, so that no intrusive closingnoises can penetrate into the vehicle interior.

Embodiments of the present disclosure provide a valve armature for asolenoid valve, at one end of which a depression is arranged, whichaccommodates a closing element having a closing member and interactingwith a valve seat. According to the disclosure an elastic dampingelement, which damps a pulse occurring as the closing member strikes thevalve seat, is arranged between the closing member and the depression.

Furthermore, a valve cartridge for a solenoid valve is proposed, havinga pole body, a guide sleeve connected to the pole body, a valve armatureaccording to the disclosure which is coupled to a closing element and isaxially moveable and guided inside the guide sleeve against the force ofa return spring between a closed position and an open position, and avalve sleeve connected to the guide sleeve and having a valve seat,which is arranged between at least one first flow port and at least onesecond flow port. The closing element in the closed position has asealing interaction with the valve seat and interrupts a fluid flowbetween at least the one first flow port and at least the one secondflow port. In the open position the closing element is lifted off fromthe valve seat and allows the fluid flow between at least the one firstflow port and at least the one second flow port.

Various aspects of the valve armature for a solenoid valve are providedby additional features of the descriptions, drawings, and claims.

It is particularly advantageous for the elastic damping element to beembodied as an elastomer disk. This affords an easy and cost-effectiveway of manufacturing the elastic damping element. For adjusting thedamping characteristics of the elastic damping element, additionalrecesses may advantageously be provided on the disk-shaped dampingelement.

In a further advantageous development of the valve armature according tothe disclosure the closing element may be embodied as aninjection-molded plastic part, such as a polyether ether ketonecomponent (PEEK component), for example. This advantageously affords anadditional damping effect.

In a further advantageous development of the valve armature according tothe disclosure the closing element may be held in the depression byretaining means. The retaining means may be formed as isolated orcircumferential calking or flanging at the edge of the depression. Theclosing element and the elastic damping element are thereby captivelyretained in the armature before assembly of the valve armature.

In a further advantageous development of the valve armature according tothe disclosure the depression may be embodied as a blind hole, whereinthe damping element is arranged at the base of the blind hole.Furthermore, the closing element may comprise a body, the dimensions ofwhich are matched to the dimensions of the depression. The body may beof a cylindrical, solid rectangular or cuboidal shape, for example. Theclosing element can thereby be guided in the depression virtually freeof play. The closing member may furthermore be formed onto the body. Theclosing member may be embodied as a spherical cap, for example. Thevalve seat may be embodied, for example, as a hollow truncated cone.

The body may be of a cylindrical, solid rectangular or cuboidal shape,for example. The closing element can thereby be guided in the depressionvirtually free of play. The closing member may furthermore be formedonto the body. The closing member may be embodied as a spherical cap,for example. The valve seat may be embodied, for example, as a hollowtruncated cone.

In a further advantageous development of the valve armature according tothe disclosure the body may be formed as an elastic damping element. Thebody formed as an elastic element may comprise a socket, whichaccommodates the closing member. The closing member may be held in thesocket of the body, for example, by hot deformation. Alternatively, theclosing member may be held in the socket of the body by way of a clippedconnection.

Exemplary embodiments of the disclosure are represented in the drawingand are explained in more detail in the following description. In thedrawing the same reference numerals identify components or elementswhich perform the same or similar functions.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 shows a schematic, perspective sectional representation of anexemplary embodiment of a valve cartridge according to the disclosurefor a solenoid valve with a first exemplary embodiment of a valvearmature according to the disclosure.

FIG. 2 shows a schematic, perspective sectional representation of asecond exemplary embodiment of a valve armature according to thedisclosure.

DETAILED DESCRIPTION

As can be seen from FIG. 1, the exemplary embodiment represented of avalve cartridge 1 according to the disclosure for a solenoid valvecomprises a pole body 2, a guide sleeve 4 connected to the pole body 2,a valve armature 10, which is axially moveable in the direction of thearrow and guided inside the guide sleeve 4 against the force of a returnspring 7 between a closed position and an open position and which iscoupled to a closing element 14, and a valve sleeve 6 connected to theguide sleeve 4 and having a valve seat 6.1, which is arranged between atleast one first flow port 6.2 and at least one second flow port 6.3. Onthe energizing of a solenoid assembly, not shown in more detail, that isto say when an electrical current is applied to a coil winding of thesolenoid assembly via electrical connections, a magnetic force generatedcauses the axially moveable valve armature 10 to move inside the guidesleeve 4 against the force of the return spring 7. The maximum possiblestroke of the valve armature 10 or the closing element 14 is predefinedby an air gap 3 between the pole body 2 and the valve armature 10. Ascan further be seen from FIG. 1, the closing element 14 in the closedposition shown has a sealing interaction with the valve seat 6.1 andinterrupts a fluid flow between at least the one first flow port 6.2 andat least the one second flow port 6.3. In an open position, not shown inmore detail, the closing element 14 is lifted off from the valve seat6.1 and allows the fluid flow between at least the one first flow port6.2 and at least the one second flow port 6.3.

As can further be seen from FIGS. 1 and 2, a depression 12, 12A, whichat least partially accommodates the closing element 14, 14A, having aclosing member 14.1, 14.1A and interacting with the valve seat 6.1, isarranged at one end of the valve armature 10, 10A. According to thedisclosure an elastic damping element 16, 16A, which damps a pulseoccurring as the closing member 14.1, 14.1A strikes the valve seat 6.1,is arranged between the closing member 14.1, 14.1A and the depression12, 12A.

In the first exemplary embodiment of the valve armature 10 according tothe disclosure represented in FIG. 1, the elastic damping element 16 isembodied as an elastomer disk. The elastic damping element 16 embodiedas an elastomer disk is inserted into the depression 12 in the valvearmature 10. For varying the damping properties, the damping element mayadditionally be provided with recesses. In order to obtain an additionaldamping effect, the closing element 14 may be formed as aninjection-molded plastic part, such as a PEEK part, for example. As canfurther be seen from FIG. 1, the closing element 14 is held in thedepression 12 by retaining means 18 in the form of circumferentialcalking or flanging at the edge of the depression 12. Alternatively,isolated calking or flanging may be provided at multiple points at theedge of the depression 12. Thus, at three points, which are arrangeduniformly spaced at the edge of the depression 12, for example, isolatedcalking or flanging may be provided as retaining means 18, in order tohold the closing element 14 in the depression 12.

As can further be seen from FIG. 1, the depression 12 in the exemplaryembodiment shown is embodied as a blind hole, at the base of which thedamping element 16 is arranged. In the first exemplary embodimentrepresented the closing element 14 comprises a cylindrical body 14.2,the dimensions of which are matched to the dimensions of the depression12. Moreover, a spherical cap-shaped closing member 14.1 is formed ontothe body 14.2. Other suitable geometrical shapes may naturally also beused for the depression 12 and the closing element 14. Thus the body14.2 may also be of a solid rectangular or cuboidal shape, for example,and the closing member 14.1 may be embodied, for example, as a cone ortruncated cone.

In the second exemplary embodiment of the valve armature 10A accordingto the disclosure represented in FIG. 2, the body 14.2A of the closingelement 14A is formed as an elastic damping element 16A. The body 14.2Amay be embodied as an elastic injection-molded plastic part, forexample. Here the body 14.2A comprises a socket 14.3A, whichaccommodates the closing member 14.1A. The closing member 14.1A, forexample, may be produced as a ball, cone or truncated cone, preferablyfrom hardened steel. The closing member 14.1A may be held in the socket14.3A of the body 14.2A by hot deformation or by a clipped connection,for example. In a manner similar to the first exemplary embodiment, thedepression 12A in the second exemplary embodiment shown is likewiseembodied as a blind hole. As in the first exemplary embodiment, theclosing element 14A is held in the depression 12A by retaining means 18Aembodied as circumferential calking or flanging at the edge of thedepression 12A. Alternatively, isolated calking or flanging may beprovided at multiple points at the edge of the depression 12A.

As can further be seen from FIG. 1, the valve cartridge 1 with the firstor second exemplary embodiment of the valve armature 10, 10A may becalked by way of a valve bushing 5 in a corresponding seating bore of ahydraulic block not further represented. Moreover, a radial filter 8 isarranged in the area of at least the one second flow port 6.3 in thevalve sleeve 6, in order to filter dirt particles out of the fluid flow.

The exemplary embodiment shown relates to a valve cartridge 1 for anormally closed solenoid valve. The valve armature 10, 10A according tothe disclosure may also be used, however, for a valve cartridge of anormally open solenoid valve, not shown further, in order to damp theclosing noise.

Embodiments of the present disclosure provide a valve armature and avalve cartridge for a solenoid valve, which through the use of anelastic damping element between the closing member of a closing elementand a depression in the valve armature advantageously damp the pulseoccurring as the closing member strikes the valve seat, and thus reducethe structure-borne noise in the vehicle.

The invention claimed is:
 1. A valve armature assembly for a solenoidvalve, comprising: an armature body that defines a depression located inone end of the armature body; a closing element received in thedepression and including a closing member configured to interact with avalve seat; and an elastic damping element that is a separate structurefrom the closing member and is positioned in the depression between theclosing member and the armature body, the elastic damping element beingconfigured and arranged to damp pulses resulting from the closing memberstriking the valve seat, wherein the elastic damping element is anelastomer disk, and wherein the elastic damping element includes aplurality of recesses.
 2. The valve armature assembly as claimed inclaim 1, wherein the closing element is an injection-molded plasticpart.
 3. The valve armature assembly as claimed in claim 1, furthercomprising at least one retaining element that holds the closing elementin the depression.
 4. The valve armature assembly as claimed in claim 3,wherein the at least one retaining element is either (i) an isolatedcalking, (ii) a circumferential calking, or (iii) a flanging located atan edge of the depression.
 5. The valve armature assembly as claimed inclaim 1, wherein: the depression is a blind hole; and the elasticdamping element is positioned at a base of the blind hole.
 6. The valvearmature assembly as claimed in claim 1, wherein at least a portion of aclosing element body of the closing element has dimensions matched todimensions of at least a portion of the depression.
 7. The valvearmature assembly as claimed in claim 6, wherein the closing member isintegrally formed onto the closing element body.